Free agent defensive end Mario Williams said he was so nervous when it came time to sign his contract with the Bills, he almost forgot his name.

No one in Buffalo will soon forget.

Williams was introduced at a news conference yesterday after signing a contract touted as the richest ever given to an NFL defensive player — a deal worth up to $100 million with $50 million guaranteed, according to his agent, Ben Dogra.

The deal was agreed to yesterday afternoon after two days of talks. Williams had been in Buffalo since the NFL’s free agency period opened Tuesday, having been flown in from his home in North Carolina.

Selected first overall in the 2006 draft by Houston, Williams had a franchise-best 53 sacks in six seasons with the Texans.

CHIEFS: Running back Peyton Hillis, dogged in Cleveland last year by reports that he might want to retire and even try a new career, will get a fresh start.

The Chiefs, determined to upgrade the second-lowest scoring offense in the NFL, formally announced they had signed Hillis to a one-year contract, for a reported $3 million.

REDSKINS: Free agent safety Brandon Meriweather has signed a two-year, $6 million deal as Washington began the task of replacing last year’s safety tandem of LaRon Landry and Oshiomogho Atogwe.

COWBOYS: The team has reached a deal with free agent safety Brodney Pool. Terms were not disclosed.

Poole played the last two seasons for the Jets after five seasons with Cleveland, where he played for Cowboys defensive coordinator Rob Ryan and their new secondary coach Jerome Henderson.

BUCCANEERS: Tampa Bay has signed free agent quarterback Dan Orlovsky to a two-year contract to serve as Josh Freeman’s backup.

VIKINGS: The team said cornerback Chris Cook’s acquittal on assault charges has opened the door for him to return to the team.

BEARS: General manager Phil Emery said it’s too soon to say if recently acquired Pro Bowl receiver Brandon Marshall will be suspended because of an allegation that he struck a woman at a New York City nightclub.

The Bears acquired Marshall from Miami for two third-round draft picks Tuesday, giving them the No. 1 receiver they’d been lacking, but news of the nightclub incident surfaced hours later.